Automated instruments can be used for analyzing samples with respect to various clinical-chemical and immunochemical analysis items. The instruments may include more than one work cell for performing processing steps. Each of the processing steps can be related to various kinds of analytical methods, and pre-analytical and/or post-analytical processing steps for preparing sample analysis and storing the samples (e.g., for further processing at a later stage).
In the course of automated sample processing, samples or aliquots thereof can be transported from one work cell to another so that individual portions can be withdrawn and/or various fluids such as, for example, reagents, diluents and buffers can be added to the samples. In automated instruments, vessels containing the samples can be transported via sample racks holding the vessels. Specifically, one rack can hold one vessel (single holder) or a plurality of vessels (multiple holders) serially arranged with respect to each other. In automated instruments, a dedicated transporting device can be used for transporting the sample racks between the various work cells. Examples of such transporting devices are described in U.S. Pat. No. 6,202,829 B1 and European Patent Application No. 1460431 A2.
The use of a single rack format (rack size) in the analytical instrument may be limited because different work cells may require different rack formats. Different rack formats may require time consuming and expensive reformatting operations in advance to their use.
Accordingly, alternative devices for transporting sample racks of different formats between various work cells in an analytical instrument may be desired.